Say in accounts REST API module where the gpgkeys REST endpoints are bound

The com.google.gerrit.server.restapi.account.Module class binds all
acoount REST endpoints except the gpgkeys REST endpoints. Readers of the
com.google.gerrit.server.restapi.account.Module class may not except
that there is another class that binds additional account REST
endpoints. Add a comment that makes them aware that the gpgkeys REST
endpoints are bound somewhere else (change Idbab00a52 moved the gpgkeys
REST endpoints into an own module).

Change-Id: Ic48c65069f78d9614292d40ae476a646af754fbd
Signed-off-by: Edwin Kempin <ekempin@google.com>

java/com/google/gerrit/server/restapi/account/Module.java

@@ -107,6 +107,8 @@ public class Module extends RestApiModule {
     get(ACCOUNT_KIND, "external.ids").to(GetExternalIds.class);
     post(ACCOUNT_KIND, "external.ids:delete").to(DeleteExternalIds.class);
 
+    // The gpgkeys REST endpoints are bound via GpgApiModule.
+
     factory(AccountsUpdate.Factory.class);
   }